In the related art, as a refrigeration cycle apparatus equipped with an expander that recovers the fluid energy as power during its expansion process, for example, there is a refrigeration cycle apparatus equipped with a first compressor that is driven by an electric motor to compress refrigerant, a radiator that rejects the heat of the refrigerant compressed by the first compressor, an expander that decompresses the refrigerant that has passed through the radiator, an evaporator in which the refrigerant decompressed by the expander evaporates, and a second compressor that is driven by the expansion power recovered in the expander and has a discharge side connected to a suction side of the first compressor (for example, refer to Patent Literature 1).
Additionally, there is a refrigeration cycle apparatus equipped with a first compressor, a radiator that rejects the heat of refrigerant compressed by the first compressor, an expander that decompresses the refrigerant that has passed through the radiator, an evaporator in which the refrigerant decompressed by the expander evaporates, and a supercharger (a second compressor) that raises the pressure of the refrigerant evaporated in the evaporator and supplies the refrigerant to the first compressor (for example, refer to Patent Literature 2).